Peter Protzman Desk  

I have this somewhat rare Herman Miller Peter Protzman Desk sans the plastic sided drawers and middle pencil/pen drawer (plastic sided drawers broke in the late 70's).
HM only made this desk for one year - According to my family member it proved too difficult to mass produce. Apparently the variation in the zebrawood made it difficult to match the desk surface to the drawers and the thick 1.5 inch bent plywood was difficult, at the time, to bend and keep the plys stuck together.
A family member worked for Herman Miller in the 70's and got this as is off the line- thus no tags or documentation.
It's never been refinished - doesn't need it. The zebrawood plywood is in near perfect condition.
Any idea of how much something like this is worth?
(sorry, not intending to use this forum as a mechanism to sell anything - just excited to chat w/ fellow design/mod furniture geeks).